The correct answer is option 2: 2.6% more.

To understand why, let`s break down the process step by step:

1. The shopkeeper gives a 10% discount on the item, which means the customer only has to pay 90% of the marked price.

- Actual price after the first discount: 2000 * 0.9 = 1800

2. The shopkeeper then gives an additional 5% discount on the item, which means the customer only has to pay 95% of the price after the first discount.

- Actual price after the second discount: 1800 * 0.95 = 1710

3. Next, the shopkeeper adds a 20% GST (Goods and Services Tax) on the item.

- Actual price after adding GST: 1710 + (1710 * 0.2) = 2052

Therefore, the customer has to pay 2052, which is 2.6% more than the marked price of 2000.